12,524 research outputs found

    Testing the Forecasting Performance of Ibex 35 Option-implied Risk-neutral Densities

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    Published also as: Documento de Trabajo Banco de España 0504/2005.risk-neutral densities, forecasting performance

    From Locational Fundamentals to Increasing Returns: The Spatial Concentration of Population in Spain, 1787-2000

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    Does population follow the same inverted-U pattern of concentration/dispersion that has been found in the case of economic activity in the long run? In this paper we present the evidence for eight European countries during the nineteenth and twentieth centuries and find that, contrary to the inverted-U hypothesis, population has shown a steady, long-run trend towards concentration. After that, we estimate population density and population growth equations for the case of one of these countries, Spain from 1787 to 2000. Our results suggest that locational fundamentals (such as natural endowments) explain the distribution of population before industrialization and that industrialization reinforced the pre-existing regional population disparities, especially as the share of increasing-returns sectors in the Spanish economy became significant (that is, mainly during the twentieth century).economic geography, population history, locational fundamentals, increasing returns

    Nearby supernova host galaxies from the CALIFA Survey: II. SN environmental metallicity

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    The metallicity of a supernova (SN) progenitor, together with its mass, is one of the main parameters that rules their outcome. We present a metallicity study of 115 nearby SN host galaxies (0.005<z<0.03) which hosted 142 SNe using Integral Field Spectroscopy (IFS) from the CALIFA survey. Using O3N2 we found no statistically significant differences between the gas-phase metallicities at the locations of the three main SN types (Ia, Ib/c and II) all having ~8.50±\pm0.02 dex. The total galaxy metallicities are also very similar and we argue that this is because our sample consists only of SNe discovered in massive galaxies (log(M/Msun)>10 dex) by targeted searches. We also found no evidence that the metallicity at the SN location differs from the average metallicity at the GCD of the SNe. By extending our SN sample with published metallicities at the SN location, we studied the metallicity distributions for all SN subtypes split into SN discovered in targeted and untargeted searches. We confirm a bias toward higher host masses and metallicities in the targeted searches. Combining data from targeted and untargeted searches we found a sequence from higher to lower local metallicity: SN Ia, Ic, and II show the highest metallicity, which is significantly higher than SN Ib, IIb, and Ic-BL. Our results support the picture of SN Ib resulting from binary progenitors and, at least part of, SN Ic being the result of single massive stars stripped of their outer layers by metallicity driven winds. We studied several proxies of the local metallicity frequently used in the literature and found that the total host metallicity allows for the estimation of the metallicity at the SN location with an accuracy better than 0.08 dex and very small bias. In addition, weak AGNs not seen in total spectra may only weakly bias (by 0.04 dex) the metallicity estimate from integrated spectra. (abridged)Comment: 24 pages, 16 Figures, 13 Tables, Accepted in A&

    What's wrong with Psychology, anyway?

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    This chapter considers various factors that have been responsible for the comparatively slow development of psychology into a cumulative empirical science. Special attention is devoted to correctable methodological mistakes, the over-reliance upon significance testing (and the fact that, in psychology, the null hypothesis is almost always false), and an analysis of the concept of replication

    Early Labour Market Returns to College Subjects

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    This paper aims at estimating early labour market outcomes of Italian university graduates across college subjects. We devote great attention to endogenous selection issues using alternative methods to control for potential self-selection associated with the choice of the degree subject in order to unravel the causal link between college major and subsequent outcomes in the labour market. Our results suggest that “quantitative” fields (i.e. Sciences, Engineering and Economics) increase not only the speed of transition into the first job and employment probability but also early earnings, conditional on employment.University to work transition; College subject; Self-selection; Returns to education

    Specialization and Variety in Repetitive Tasks: Evidence from a Japanese Bank

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    Sustaining operational productivity in the completion of repetitive tasks is critical to many organizations' success. Yet research points to two different work-design related strategies for accomplishing this goal: specialization to capture the benefits of repetition or variety to keep workers motivated and allow them to learn. In this paper, we investigate how these two strategies may bring different benefits within the same day and across days. Additionally, we examine the impact of these strategies on both worker productivity and workers' likelihood of staying at a firm. For our empirical analyses, we use two and a half years of transaction data from a Japanese bank's home loan application processing line. We find that over the course of a single day, specialization, as compared to variety, is related to improved worker productivity. However, when we examine workers' experience across days we find that variety, or working on different tasks, helps improve worker productivity. We also find that workers with higher variety are more likely to stay at the firm. Our results identify new ways to improve operational performance through the effective allocation of work.Job Design, Learning, Productivity, Specialization, Turnover, Variety, Work Fragmentation

    R&D Drivers in Young Innovative Companies

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    This paper examines the determinants of young innovative companies' (YICs) R&D activities taking into account the autoregressive nature of innovation. Using a large longitudinal dataset comprising Spanish manufacturing firms over the period 1990-2008, we find that previous R&D experience is a fundamental determinant for mature and young firms, albeit to a smaller extent in the case of the YICs, suggesting that their innovation behaviour is less persistent and more erratic. Moreover, our results suggest that firm and market characteristics play a distinct role in boosting the innovation activity of firms of different age. In particular, while market concentration and the degree of product diversification are found to be important in fostering R&D activities in the sub-sample of mature firms only, YICs' spending on R&D appears to be more sensitive to demand-pull variables, suggesting the presence of credit constraints. These results have been obtained using a recently proposed dynamic type-2 tobit estimator, which accounts for individual effects and efficiently handles the initial conditions problem.R&D, innovation, Young Innovative Companies (YICs), dynamic type-2 tobit estimator

    Generalized Transmuted Family of Distributions: Properties and Applications

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    We introduce and study general mathematical properties of a new generator of continuous distributions with two extra parameters called the Generalized Transmuted Family of Distributions. We investigate the shapes and present some special models. The new density function can be expressed as a linear combination of exponentiated densities in terms of the same baseline distribution. We obtain explicit expressions for the ordinary and incomplete moments and generating function, Bonferroni and Lorenz curves, asymptotic distribution of the extreme values, Shannon and R´enyi entropies and order statistics, which hold for any baseline model. Further, we introduce a bivariate extension of the new family. We discuss the different methods of estimation of the model parameters and illustrate the potential application of the model via real data. A brief simulation for evaluating Maximum likelihood estimator is done. Finally certain characterziations of our model are presented
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